This invention is directed to a stroller and, in particular, to a stroller that can be folded for storage.
In recent years, many developments have been made with respect to strollers. In particular, the folding features and handleability of strollers have been improved and strollers have been developed for use while jogging or in-line skating, over rugged terrain and through snow and sand.
While some previously available strollers are foldable, many folding systems are complex both in terms of use and in terms of manufacture. The various cross members required to permit folding while maintaining stroller frame rigidity can increase the weight of the stroller to undesirable levels and add to the bulk of the folded trailer.
The use of strollers is often uncomfortable because the gripping portion of the stroller handle is at an incorrect height for the user. While some strollers include mechanisms for handle height adjustment, these mechanisms are often not user friendly. The mechanisms generally require the installation of an adjustment connection near the gripping portion which can weaken the handle and which complicates stroller construction, thereby increasing stroller cost.
A common problem with previous strollers is the tendency for their wheels to move out of alignment, thereby adversely affecting stroller tracking. In particular, the front wheel or wheels can become off-centre or out of parallel position relative to the rear wheels.
Many strollers do not provide a mechanism for adjusting the stroller""s center of gravity, except by adjusting the position of the child or bags etc. loaded into the stroller. Therefore, the weight on the front forks can""t be reliably adjusted and the performance of the stroller cannot be controlled in this respect.
A stroller is needed that overcomes at least some of these problems of previous strollers.
The stroller of the present invention overcomes some of the problems set out above with respect to previous strollers. A stroller folding system is disclosed which is simple with respect to both use and manufacture and includes foldable cross members that are light-weight and durable. Stroller mechanisms are also disclosed for correcting tracking problems and to select handle height.
One stroller according to the present invention can be folded for storage and transport. The stroller includes three main structural units that pivot relative to each other at closely positioned pivotal axes. The pivotal axes are defined by a pair of brackets aligned one on each side of the stroller and into which each of the three main structural units are connected. This permits stroller construction to be simplified since only one pair of brackets is needed to be formed and mounted into the frame and many mechanical connections on the stroller are made through that pair of brackets. The procedure by which the stroller is folded is also simplified by use of the pair of aligned brackets in the present stroller.
In accordance with a broad aspect of the present invention, there is provided a stroller having a forward end and a rear end and a long axis extending through the forward end and the rear end, the stroller comprising: a plurality of wheels for supporting the stroller including at least one forward wheel positioned forward of the stroller""s centre of gravity and rear wheels; a frame supported by the wheels having main frame members including front wheel supports for engaging the at least one front wheel, a handle bar for grasping and moving the stroller and rear wheel supports for engaging the rear wheels; a connecting bracket on each side of the frame having connected thereto the main frame members and at least two of the main frame members being pivotally moveable at their connection to the connecting brackets and the connecting bracket positioned to permit the at least two main frame members to pivot about the bracket such that the stroller can be manipulated between an upright position and a folded position; and a locking means for releasably locking the stroller in the upright position.
As will be appreciated, in a three-wheeled stroller there will generally be a single front wheel supported on front forks and a pair of rear wheels. In a four-wheeled stroller the frame will generally be supported on four wheels, with two forward and two at the rear. Generally, the rear wheel supports will be connected such that they pivot together during manipulation of the frame, as will the front wheel supports in a four-wheeled stroller.
In one embodiment, the front wheel supports are rigidly connected to the connecting brackets, while the handle and rear wheel supports are pivotally connected to the connecting brackets. This arrangement provides a compact configuration when the stroller is in the folded position. In addition, this has been found to particularly facilitate the unfolding operation of the stroller since by simply lifting the folded stroller by the front wheel supports, the rear wheel supports will rotate down and away and the stroller will automatically be in a configuration in which it can be supported on its wheels.
The frame of the stroller can be formed of various rigid materials including, but not limited to, aluminum or polymeric tubing, rods or bars. The frame can include frame cross members for providing locking the stroller into a rigid position or maintaining positioning of stroller components. These frame cross members can also be formed of aluminum or polymeric tubing, rods or bars or can alternately be formed of flexible cables, as will be discussed in more detail. The frame supports a seat for accepting one or more children and, if desired, a covering or sunshade to shelter the seat. In one embodiment, the seat includes a drink bottle pocket formed in the forward part of the seat, which is accessible by a child positioned in the seat. Preferably the pocket is positioned in the seat in the area between a child passenger""s legs. In another embodiment, the sunshade includes a visor including a stiffening member permitting the visor to be set in a stationary in-use position. Preferably, the stiffening member is adjustable such that it can be moved between the stationary in-use position and a stored position.
The handle can be formed in any way to facilitate grasping and control of the stroller. Preferably, the handle is height adjustable to be comfortable for users of various height. In one embodiment, the connecting bracket includes a mechanism for handle height adjustment. Preferably, the mechanism is incorporated into the handle""s pivotal connection to the connecting bracket.
To provide frame rigidity the rear supports can have extending therebetween a cross bar or an axle. The frame can also include other cross members such as one extending between the front wheel supports and the rear supports.
The wheels are selected to support the frame and permit it to be rolled as by pushing. The wheels can be of any desired size. Preferably, the wheels are mounted to rotate in planes parallel with the long axis of the stroller and are restricted from pivoting out of these planes. A relative wheel positioning mechanism can be mounted on the stroller to permit adjustment of relative wheel alignment and/or spacing for tracking or center of gravity adjustment.
The locking means can be any mechanism or part for locking frame members in an upright position. As an example, the locking means can be pins, fasteners, overcenter mechanisms, etc.
Another stroller according to the present invention includes at least one flexible elongate cross member extending to act between main frame members. The cross member is connected to act between main frame members to maintain or limit their spacing and is particularly useful for extending between main frame members that are pivotable relative to each other and for being placed in tension between main frame members. The flexible elongate cross member can in some applications replace a stiff cross member, thereby reducing stroller complexity, folded size and weight.
Thus, according to another broad aspect of the present invention, there is provided a stroller having a forward end and a rear end and a long axis extending through the forward end and the rear end, the stroller comprising: a plurality of wheels for supporting the stroller including at least one front wheel positioned forward of the stroller""s centre of gravity and rear wheels; a frame supported by the wheels having main frame members including (a) front wheel supports for engaging the at least one front wheel, (b) a handle bar for grasping and moving the stroller and (c) rear supports securing and extending upwardly from the rear wheels; and a flexible, elongate cross member extending to act between at least two of the main frame members to control the spacing between the main frame members.
The flexible elongate cross member can be, for example, a strap, a cord, a chain or a cable. Preferably, the flexible elongate member is substantially inextensible so that the length of the cross member once in tension between two main frame members will limit the degree to which they can be separated. However, in one embodiment, the cross member has a capability of limited stretch under loads beyond a selected level so that it provides a suspension effect.
In one embodiment, the flexible elongate member is secured in fixed positions on the at least two main frame members between which it extends. In another embodiment, the flexible elongate member is secured to stroller components connected to main frame members, but through which the flexible elongate member can act to adjust the spacing between the main frame members. In another embodiment, the stroller includes a tension adjustment means for selecting the tension in the flexible elongate member as it extends between the main frame members. Various tension adjustment means such as, for example, threaded connections, turn buckles, clamps and levers are useful with the stroller.
In one stroller according to the present invention, the flexible elongate member is included in an over-center mechanism for providing frame rigidity between two main frame members. In another stroller according to the present invention, the flexible elongate member acts between the front wheel supports and the rear supports to limit the spacing therebetween.
There are various situations wherein it is desirable to adjust the spacing between the front and rear wheels. For example, the stroller center of gravity, and thereby the weight placed on the front wheel or wheels, can be controlled in part by adjusting the space between the front and rear wheels. In addition, due to manufacturing or wear and tear, the spacing and alignment between the wheels can tend to cause a stroller to lose its ability to track straight Thus, another stroller according to the present invention includes a means for relative wheel positioning, for example, to adjust stroller center of gravity and/or tracking.
Thus, according to yet another broad aspect of the present invention, there is provided a stroller having a forward end and a rear end and a long axis extending through the forward end and the rear end, the stroller comprising: a plurality of wheels for supporting the stroller including at least one front wheel positioned forward of the stroller""s centre of gravity, a left rear wheel and a right rear wheel; a frame supported by the wheels including front wheel supports securing and extending rearwardly from the at least one front wheel, a handle bar for grasping and moving the stroller, a left rear support securing and extending upwardly from the left rear wheel and a right rear support securing and extending upwardly from the right rear wheel; and a relative wheel positioning means for selecting and maintaining the spacing of the at least one front wheel relative to at least one of the left rear wheel and the right rear wheel.
The relative wheel positioning means is useful for strollers supported on both three and four wheels. In a three-wheeled stroller, the relative wheel positioning means includes a mechanism for adjusting the spacing between the front wheel and each of the left and right rear wheels. In a four-wheeled stroller, the relative wheel positioning means includes a mechanism for adjusting the spacing between the right-side front and rear wheels and the left-side front and rear wheels.
In one embodiment, the relative wheel positioning means is two elongate members each one extending to act between the front wheel supports and one of the rear supports to control the spacing therebetween. In a three-wheeled stroller each elongate member extends between the front forks and one of the rear supports. In a four wheeled stroller, the elongate members can extend between the front and rear wheels in a parallel or a cross pattern. Each of the elongate members is substantially inextensible. The elongate members can each include a mechanism for selecting its extended length. Preferably, the mechanism for adjusting the length of the elongate member can be actuated to adjust the length while the elongate member remains connected between the front wheel support and its rear support. The mechanism for adjusting the length can be a threaded connection in the elongate member or between the elongate member and one of the supports, a telescoping member, a turn buckle, etc. In one embodiment, while the elongate members are substantially inextensible, they have limited elasticity such that loads over a selected level will cause the elongate members to stretch slightly to provide for suspension effect. In one embodiment, the elongate members each include a flexible elongate portion. The flexible elongate portion can be for example, formed of cable, chain, strap, etc. The use of a flexible portion facilitates folding of the stroller.
According to another broad aspect of the present invention, there is provided a stroller having a forward end and a rear end and a long axis extending through the forward end and the rear end, the stroller comprising: a plurality of wheels for supporting the stroller including at least one front wheel positioned forward of the stroller""s centre of gravity, a left rear wheel and a right rear wheel; a frame supported by the wheels including front wheel supports securing and extending rearwardly from the at least one front wheel, a left rear support securing and extending upwardly from the left rear wheel, a right rear support securing and extending upwardly from the right rear wheel; and a handle bar for grasping and moving the stroller, the handle bar being connected into the frame by a pivotal connection and the pivotal connection being incorporated into a mechanism for handle height adjustment with respect to the stroller.
In one embodiment, the pivotal connection includes a pin secured to the handle and slidably engaged in a slot on the frame. The pin is slideably moveable in the slot between a first position and a second position, to drive the handle against a fixed fulcrum such that the gripping portion of the handle is moved into a higher position when the pin is in the first position and the gripping portion of the handle is in a lower position when the pin is in the second position. A releasable lock is provided to maintain the pin in the first position or the second position during use.
The features of (i) a pair of brackets onto which all main frame members are secured and about which selected main frame members pivot for folding; (ii) flexible cross members, (iii) relative wheel positioning means and (iv) handle height adjustment can all be used on the same stroller or individually or in combination on any particular stroller, as desired.